Replace common segment/offset pairs with struct segoff_s.

[seabios.git] / src / util.c

diff --git a/src/util.c b/src/util.c
index 7358040ed322560f0f7e1c31a16a29d0a6976552..841c00a7ac3ecbd103dc5d79f0af4f1b423cc04c 100644 (file)
--- a/src/util.c
+++ b/src/util.c
@@ -1,6 +1,6 @@
 // Misc utility functions.
 //
-// Copyright (C) 2008  Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2008,2009  Kevin O'Connor <kevin@koconnor.net>
 //
 // This file may be distributed under the terms of the GNU LGPLv3 license.
 
@@ -17,8 +17,10 @@ call16(struct bregs *callregs)
     asm volatile(
 #if MODE16 == 1
         "calll __call16\n"
+        "cli\n"
+        "cld"
 #else
-        "calll __call16_from32\n"
+        "calll __call16_from32"
 #endif
         : "+a" (callregs), "+m" (*callregs)
         :
@@ -28,12 +30,9 @@ call16(struct bregs *callregs)
 inline void
 call16big(struct bregs *callregs)
 {
-    extern void __force_link_error__call16big_only_in_32bit_mode();
-    if (MODE16)
-        __force_link_error__call16big_only_in_32bit_mode();
-
+    ASSERT32();
     asm volatile(
-        "calll __call16big_from32\n"
+        "calll __call16big_from32"
         : "+a" (callregs), "+m" (*callregs)
         :
         : "ebx", "ecx", "edx", "esi", "edi", "cc", "memory");
@@ -43,40 +42,18 @@ inline void
 __call16_int(struct bregs *callregs, u16 offset)
 {
     if (MODE16)
-        callregs->cs = GET_SEG(CS);
+        callregs->code.seg = GET_SEG(CS);
     else
-        callregs->cs = SEG_BIOS;
-    callregs->ip = offset;
+        callregs->code.seg = SEG_BIOS;
+    callregs->code.offset = offset;
     call16(callregs);
 }
 
-inline void
-call16_simpint(int nr, u32 *eax, u32 *flags)
-{
-    extern void __force_link_error__call16_simpint_only_in_16bit_mode();
-    if (!MODE16)
-        __force_link_error__call16_simpint_only_in_16bit_mode();
-
-    asm volatile(
-        "stc\n"
-        "int %2\n"
-        "pushfl\n"
-        "popl %1\n"
-        "cld\n"
-        "cli\n"
-        : "+a"(*eax), "=r"(*flags)
-        : "i"(nr)
-        : "cc", "memory");
-}
-
 // Switch to the extra stack in ebda and call a function.
 inline u32
 stack_hop(u32 eax, u32 edx, u32 ecx, void *func)
 {
-    extern void __force_link_error__stack_hop_only_in_16bit_mode();
-    if (!MODE16)
-        __force_link_error__stack_hop_only_in_16bit_mode();
-
+    ASSERT16();
     u16 ebda_seg = get_ebda_seg(), bkup_ss;
     u32 bkup_esp;
     asm volatile(
@@ -92,7 +69,7 @@ stack_hop(u32 eax, u32 edx, u32 ecx, void *func)
         // Restore segments and stack
         "movw %w3, %%ds\n"
         "movw %w3, %%ss\n"
-        "movl %4, %%esp\n"
+        "movl %4, %%esp"
         : "+a" (eax), "+d" (edx), "+c" (ecx), "=&r" (bkup_ss), "=&r" (bkup_esp)
         : "i" (EBDA_OFFSET_TOP_STACK), "r" (ebda_seg), "m" (*(u8*)func)
         : "cc", "memory");
@@ -117,6 +94,68 @@ checksum(void *buf, u32 len)
     return checksum_far(GET_SEG(SS), buf, len);
 }
 
+size_t
+strlen(const char *s)
+{
+    if (__builtin_constant_p(s))
+        return __builtin_strlen(s);
+    const char *p = s;
+    while (*p)
+        p++;
+    return p-s;
+}
+
+// Compare two areas of memory.
+int
+memcmp(const void *s1, const void *s2, size_t n)
+{
+    while (n) {
+        if (*(u8*)s1 != *(u8*)s2)
+            return *(u8*)s1 < *(u8*)s2 ? -1 : 1;
+        s1++;
+        s2++;
+        n--;
+    }
+    return 0;
+}
+
+// Compare two strings.
+int
+strcmp(const char *s1, const char *s2)
+{
+    for (;;) {
+        if (*s1 != *s2)
+            return *s1 < *s2 ? -1 : 1;
+        if (! *s1)
+            return 0;
+        s1++;
+        s2++;
+    }
+}
+
+inline void
+memset_far(u16 d_seg, void *d_far, u8 c, size_t len)
+{
+    SET_SEG(ES, d_seg);
+    asm volatile(
+        "rep stosb %%es:(%%di)"
+        : "+c"(len), "+D"(d_far)
+        : "a"(c)
+        : "cc", "memory");
+}
+
+inline void
+memset16_far(u16 d_seg, void *d_far, u16 c, size_t len)
+{
+    len /= 2;
+    SET_SEG(ES, d_seg);
+    asm volatile(
+        "rep stosw %%es:(%%di)"
+        : "+c"(len), "+D"(d_far)
+        : "a"(c)
+        : "cc", "memory");
+}
+
 void *
 memset(void *s, int c, size_t n)
 {
@@ -134,18 +173,35 @@ memcpy_far(u16 d_seg, void *d_far, u16 s_seg, const void *s_far, size_t len)
         "movw %%ds, %w0\n"
         "movw %w4, %%ds\n"
         "rep movsb (%%si),%%es:(%%di)\n"
-        "movw %w0, %%ds\n"
+        "movw %w0, %%ds"
         : "=&r"(bkup_ds), "+c"(len), "+S"(s_far), "+D"(d_far)
         : "r"(s_seg)
         : "cc", "memory");
 }
 
 void *
+#undef memcpy
 memcpy(void *d1, const void *s1, size_t len)
+#if MODE16 == 0
+#define memcpy __builtin_memcpy
+#endif
 {
-    u8 *d = (u8*)d1, *s = (u8*)s1;
-    while (len--)
-        *d++ = *s++;
+    SET_SEG(ES, GET_SEG(SS));
+    void *d = d1;
+    if (((u32)d1 | (u32)s1 | len) & 3) {
+        // non-aligned memcpy
+        asm volatile(
+            "rep movsb (%%esi),%%es:(%%edi)"
+            : "+c"(len), "+S"(s1), "+D"(d)
+            : : "cc", "memory");
+        return d1;
+    }
+    // Common case - use 4-byte copy
+    len /= 4;
+    asm volatile(
+        "rep movsl (%%esi),%%es:(%%edi)"
+        : "+c"(len), "+S"(s1), "+D"(d)
+        : : "cc", "memory");
     return d1;
 }